Mikroelektronika MIKROE-350 データシート

Optimizer has been added to extend the compiler usability, cut down the amount of
code generated and speed-up its execution. The main features are:

All expressions that can be evaluated in the compile time (i.e. are constant) are
being replaced by their results. (3 + 5 -> 8); 

When a constant value is being assigned to a certain variable, the compiler recog-
nizes this and replaces the use of the variable by constant in the code that follows,
as long as the value of a variable remains unchanged. 

The compiler recognizes that two variables have the same value and eliminates one
of them further in the code. 

The compiler "recognizes" if two expressions yield the same result and can there-
fore eliminate the entire computation for one of them. 

The code snippets that are not being used elsewhere in the programme do not affect
the final result of the application. They are automatically removed. 

Temporary registers ("Stacks") are being used more rationally, allowing VERY com-
plex expressions to be evaluated with a minimum stack consumption. 

No local variables are being used if their result does not affect some of the global or
volatile variables. 

Code generation is more consistent and more attention is payed to implement spe-
cific solutions for the code "building bricks" that further reduce output code size. 

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- SOFTWARE AND HARDWARE SOLUTIONS FOR EMBEDDED WORLD

CHAPTER 3